Pectic substance and process of making the same



UNITED STATES- PATENT", or-rice.

rnnnmcx WILLIAM mean, or RIVERSIDE, cann'omwra. rncrrc sunsrancn AND rnocnss or MAKING rm: smn

Ho Drawing.

' this purpose which is in convenient condition for use and is extremely efficient as a gelatinizin agent. I

Another object of my invention is to provide a pectic substance in substantially anhydrous condition and containing a peptizing agent, so as to be in convenient condition for immediateuse for mixing with the sugar and flavoring materials, together with the requisite amount of water and coagulating agent, if desired. In making the pectic substance referred to, I may use any suitable fruits or vegetables. I have found that the waste lemon pulp constituting a by-product of the manufacture of citric acid is a suitable source of said substance and I will describe my process of making said substance using such waste lemon pulp, it being understood, however, that the process is applicable to other citrus ordeciduouis fruits, or to vegetables.

The process may be carried out as follows:

(1). The lemon pulp is ground as fine as possible by passing through a meat.

grinder;

(2) This finely ground pulp is now soaked for ten to thirty minutes with about three or four times its volume of water;

(3) The soaked pulp is then dewatered in any convenient manner. This removes practically all of the slime-like material which interferes with the subsequent operations;

.(4) The dewatered pulp is now introduced into a dilute solution of caustic soda whose concentration lies between 01.2 and 0.4% NaOH (the volume of solution can to advantage be about two and a half times the weight of the pulp). The mass is gently stirred for about fifteento thirty minutes at about 40 C. Extraction is equally good at any temperature up 'to 80 C; at 40 the extraction is more rapid than at atmospheric temperature. The solution contains the al- Speciflcation of Letters IPatent Patented Mar. 28, 19522..

Application filed November 8, 1920. erial No. 422,538.

kali extract of pectic substance. This so lution is now removed from the pulp by straining or filtration; and set aside; y

(5.) The remaining pulp is now again treated with an additional equal volume of dilute caustic soda (same concentration as above) and stirred period of time at about the same temperature. The solution is then removed from the pulp and added to'thesolution set aside from the first extraction. v The pulp has now been exhausted of the as above for the same greater portion of its pectic substance. It

may be again treated with additional amounts of fresh leaching fluid and this then used to leach either a new batch of pulp or another batch of partially exhausted pulp in order to build up its concentration in pectic substance.

At this point attention is called to a very essential condition of the solution. .If the pectic substance is precipitated from a solution too dilute a uniform thin-gel forms on adding the precipitating reagent. .-This gel is unfilterable and cannot be washed free of impurities and reagent; but, on the other I hand, if the solution is concentrated to'near saturation then byadding the precipitant cipitated in a globular and gelatinous form in a fine stream the pectic substance is pre resemblin very much in appearance soaked tapioca. his coagulum, or precipitate, is

very easily filtered and washed and readily dried. The concentration can very conveniently be measured by its viscosity, and the addition is so adjusted that the concentration is sufficient to ensure that when the precipitant is introduced in a fine stream the pectic substance willform into globular, gelatinous bodies. A] convenient way to ensure this is to use a solution which is nearly saturated with pectic substance'but considerable departure from saturationmay be allowed in some cases without preventlng separation of the gel into a globular mass, and this condition of separating into a globular mass on addition of the precipitate in a fine stream may be used as a test as to suficient saturation'of the pectic substance in the solution.

.A little practice, however, will enable the (6) The combined solutions from steps #5 and #4: are now preferably clarified perature, with "(which is, in thepresent examp e, apparent from the fading of thedark red color to a water yellow) andthe solution is faintly yet distinctly acid in reaction; I prefer to use, on

account of its cheapness, sulfuric acid di-.

luted to about one part of acid to four parts (7) The tapioca' like coaguluin is now freed ofits-solution by straimng or filterin and 'washing. The washing is prolonge acid used;

' (s The washed ass-.1, now dried eta temperature not in excess of 70 C. The dried mass is then ground and constitutes the finished product. This product has the physical and chemical properties which have already been enumerated.

The pectic substance produced in this manner is, or may be substantially anhydrous and is in convenient conditionv for storage, shipment and use and constitutes a" roduct'which is marketable as such, requirmg, however, the use of a peptizing or dis-- 'ersing agent when it 'is used in making it, .-or other jellies, for example, this substantially -anhydrous .pectic substance produced as abovedescribed maybe hoiled with a one-half to one per cent solution of sodium or potassium citrate, or sodium, or

potassium tartrate, or other alkali-metal salt" of an organic acid (the amount of such salt being, for example, about equal by weight to the amount of pectic substance used) to produce a colloidal'solution or dispersion to which the other constituents of the jelly are added, for example, about 65% of sugar and fruit flavoring, the resultant product, after boiling for a few minutes,

setting to a stifi jelly upon-cooling or standing from ten to twelve hours, or a rapid gelatinizing action can be effected by adding to the solution, in addition-to the above constituents, from .2 to-.5-% of citric, or tartaric acid, at or near boiling temperature, the colloidal solution then setting to a stiff jelly in a period of from five to thirty minutes.

As a matter of convenience and economy, I prefer to provide the peptizing or disersing agent in the substantially anhyrous pectic substance as itismanufactured for useand sale; for this purpose, the citric or tartaric acid, for example, in a finely ground condition, can be intimately mixed with the anhydrous duced as above described, so that the reectic substance prosultant mixture contains not only the pectic substance proper but the dispersing agent therefor, and in" orderiito produce a jelly it is only necessary to introduce this product containing a m xture of the pecticsubstance and the dispersmg agent into water, together with the necessary amount of sugar and vtic substance and sodium citrate or tartrate, may be ground together or intimately mixed until the wash-water shows no trace of the in any suitable manner, the resulting mixture so produced gives a satisfactory gel when 1% of the mixture, together with 65% of sugar, is addedto water, and, if desired, the gelatiniz'ation of the resulting solution can bemadealmost instantaneous by the additionof 1% to 1}% or' organic acid.

'It has long been known that-pectinfor pectic substance is soluble in alkali'es. It has also been known that if such an alkaline solution be made acid with any acid that a precipitation takes place. This precipitate is insoluble in dilute mineral or organicacids and cold or hotwater. I am not aware that this precipitate so obtained has ever been suggested as a pectic substancefor making jellies; in fact, it has'not been considered of value for the reason that it was irreversible, that is' it cannot be dispersed to colloidal solution by simple treatment with water. It is this generally known' fact of the physical properties of this gel'that has probably discouraged investigators from attemptingI to make any commercial use of same. y discovery that this gel could'be dispersedor peptized by means of suitable reagents, for example, an alkali-metal salt of an organic acid, enables me to utlllze this product in the manner stated.

While I prefer to use as a peptizing or V dispersing agent analkali-metal salt of an organic acid, I have found'that sodlum or potassium phosphate can 'also'be used, say 7 I, therefore, prefer. to use such alkali-- metal salts of anorganic acid, for-exam-ple, potassium or sodium citrate-or tartrate. What I claim is: "1. Acompo'sition. of matter comprising a pectic substance derived from. :truit or-ve etable matter b treatment of the latter w1th an alkaline so ution, andprecipitation with acid, and consisting of a gel irreversible to colloidal solution by treatment with water alone.

2. The composition of matter for use as a gelatinizing agent in making jellies and comprising a gel derived from fruit or vegetable material by treatment with an alkaline solution, and precipitation with acid, having the property of irreversibility to colloidal solution by treatment with water alone, said composition also including in intimate mixture with said gel a dispersing agent suflicient to effect dispersion of the said gel to colloidal solution on mixing thecomposition with water.

3. A composition of matter, as set forth in claim 2, in which said dispersing agent consists of an alkali-metal salt of an organic acid.

4:. The process which consists in treating fruit or vegetable matter with an alkaline solution, treating the resultant solution with acid to precipitate a pectic substance, removing water from the pectic substance to bring it to substantially anhydrous condition, and intimately mixing with said pectic substance sufiicient peptizing agent to disperse the said pectic substance to colloidal I solution on mixture with water.

5. The process which consists in treating fruit or vegetable matter with water to remove soluble material and slimes, treating the residue with an alkaline solution, treating the resulting solution with acid to presaid solution by the addition of acid to the solution in a fine stream,-the said solution of pectic substance being of suflicient concentration to cause a precipitate to be formed in separate globular masses, removing the precipitate from the solution, and drying the same.

In testimony whereof I have hereunto subscribed my name this 29th day of 0ctober, 1910.

FREDERICK WILLIAM' HUBER. 

